1. Field of the Invention
The present invention relates to a magnetic tape recording and/or reproducing apparatus such as a video tape recorder (VTR), a digital audio tape recorder (DAT), etc.
2. Description of the Prior Art
Video tape recorders (VTRs) or digital audio tape recorders (DATs) generally comprise a tape loading mechanism by means of which a length of the tape extending between a supply reel and a take-up reel in a tape cassette is withdrawn from the tape cassette and is then wrapped around a rotary drum by a predetermined rotational angle. The rotary drum has at least one magnetic head. The tape while being wrapped around the rotary drum is gripped by a pinch roller and a capstan and fed in a direction to perform recording and reproducing operations.
The drum is rotated by a drum motor. The capstan and two reel discs engageable by reels in the cassette are rotated by a capstan motor. The tape loading mechanism, the pinch roller and other mechanisms are operatively connected to cams of a large-diameter cam gear via a number of connecting arms and levers so as to perform predetermined operations in response to rotation of the cam gear driven by another motor.
The rotary drum, pinch roller, capstan and reel discs have their respective heights which are determined depending on the width of the tape. It is therefore impossible to minimize the overall thickness of the magnetic recording and/or reproducing apparatus by reducing the profile of the foregoing components independently from the tape width.
On the other hand, a conventional drive mechanism includes a cam gear to which a number of arms, levers and plates are connected in superposed relation to the components specified above. With this superposed arrangement, a reduction of the overall thickness and weight of the magnetic recording and/or reproducing apparatus is substantially impossible.
Furthermore, in the conventional apparatus, main parts and mechanisms, such as a drum, reel discs, a tape loading mechanism and a tape traveling mechanism, are mounted on upper and lower surfaces of a single deck. This arrangement requires a tedious and time-consuming assembling work. In addition, the parts and mechanisms are exposed so that they are likely to be damaged and unsightly in appearance. Furthermore, a foreign matter can easily get into a clearance between movable parts, causing a malfunctioning of the apparatus. The single deck structure has a relatively low rigidity and can provide only a limited degree of freedom in arranging the component parts.